1. Field of the Invention
The present invention pertains to systems for displaying data on flat panels of the matrix-addressing type.
The invention applies in particular to the display of control data in avionics. The display may be of the head-up display or head-down display types.
As the older conventional electro-mechanical instruments become obsolete, there is an ever-increasing amount of data to be displayed on the dashboard instruments of modern aircraft. Certain data displayed are essential for flight safety or for operation and should therefore be reliable and always displayed or capable of being displayed.
2. Summary of the Invention
It is an object of the invention to meet these imperative requirements through a particular structure of the display system.
According to the invention, it is proposed to make a display system on a matrix type flat panel comprising a display device consisting of the matrix type panel and matrix addressing means controlled to obtain an image resulting from an "even" image and an "odd" image interlaced with each other, the said means comprising four groups of circuits which respectively address even-numbered lines and even-numbered columns forming the even image and odd-numbered lines and odd-numbered columns forming the odd image, the said system further comprising graphic processor means to prepare the video signals to be displayed by the addressing of columns and scanning signals by line-addressing, the said graphic processor means being divided into two sub-groups, a first sub-group used to prepare the even image and a second sub-group used to prepare the odd image.
The resulting advantages give increased safety through the reduced possibility of displaying wrong data since the proposed structure makes it possible to detect data of this type by observing of the panel. This means that the structure used ensures a high level of safety compatible with very strict requirements as regards the certification of navigability. Another advantage results from the constant availability of essential data as the method used makes it possible to protect these data by reproducing them after a malfunction and thus providing for maintaining a display limited to at least this essential working data. This also means a reduction in maintenance costs because less equipment has to be dismantled.
In the prior art, the French Pat. R-A-2 571 571 describes the making of an image generator which, through an image memory, can control displays using different scannings, either circular scanning produced directly by a symbol generator or other types of scanning using the image store, for example the so-called television type of frame or interlaced scanning or matrix scanning.